Go to address bar type about:config and press enter.. now in the search bar type gfx.color
press enter. You should see the following entries with there default values.
gfx.color_management.enablev4 ----- false
gfx.color_management.mode ------- 2
gfx.color_management.rendering_intent ------ 0
gfx.color_management.display_profile ----- blank
Now before we go on tweaking the settings make sure that you are set to use Color management at the OS level. I use Fedora Linux with KDE 4.10.x which has system wide color management enable.
For Windows look under Control Panel > Color management. Make sure the OS load the correct ICC profile for the monitor that you have.
You can also use the model specific tool for this.. for e.g my Samsung SyncMaster came with software to load the correct monitor profile and color setting tools. Check you vendor web site for updates or patches for your model. Now once we have a color profiled monitor and OS ...
Toggle gfx.color_management.enablev4 --- True.
Possible values and their effects
False (default) Version 4 is not enabled
True Version 4 is enabled
gfx.color_management.rendering_intent change to -1
3 Absolute colorimetric
0 Disable color management.
1 Enable color management for rendered graphics.
2 Enable color management for tagged graphics only. (Default)
That's all it that simple to have better Photographs in Firefox, restart the web browser. If you find all this manual editing a bit of hassle use the "Color Management" add-on to do the same. Have fun :)